The commissioner shall render on the first day of July of each year a detailed and itemized account of all expenses of the commissioner's office, of all institutes held and of all money paid out for employees under the provisions hereof, all sums of money paid for prizes on exhibits and for all other purposes. For this purpose the commissioner shall keep necessary books in which an account of all money received and expended is entered, which books must be open to public inspection.   [RR 2021, c. 1, Pt. B, §55 (COR).]